In some measurement applications, multi-port vector network analyzers (VNAs) rely on power calibrations at multiple ports of the multi-port VNA. Calibrating power at multiple ports using prior art calibration techniques involves coupling a power sensor to each of the ports and making a corresponding power measurement at each of the ports. This type of power calibration involves connecting and disconnecting the power sensor multiple times, which can be time consuming, can reduce measurement repeatability, and can increase the risk of operator-induced errors. In addition, when the multiple ports have different sexes or different connector types, or if the multiple ports require substantially different power levels, more than one type of power sensor may be needed to accommodate for these differences. Reducing the number of the power measurements in the power calibration of a multi-port VNA can eliminate the need for different types of power sensors, and can increase measurement repeatability, decrease measurement errors, decrease the risk of operator induced errors, and decrease the time it takes to perform the power calibration. Accordingly, there is motivation to reduce the number of power measurements that are needed for power calibration of a multi-port VNA.